Lathe center



July 17, 1934. G. DEN 1,967,004

LATHE CENTER Filed May 23, 1933 fE-V Inventor pan/m G Bra /e 2 flltorneyiatented July 17, 1934 UNITED STATES? LATHE CENTER Daniel G. Braden,Staunton, Va.

Application May 23, 1933, Serial No. 672,483

1 Claim.

This invention relates to a lathe center, the general object of theinvention being to provide a shell and a center member rotatablyarranged in the shell with thrust bearings for the center member andmeans for adjusting the parts to take up wear.

This invention also consists in certain other features of constructionand in the combination and arrangement of the several parts to behereinafter fully described, illustrated in the accompanying drawing andspecifically pointed out in the appended claim.

In describing the invention in detail, reference will be had to theaccompanying drawing wherein like characters denote like orcorresponding parts throughout the several views, and in which:

Figure 1 is an elevation of the invention.

Figure 2 is a longitudinal sectional view therethrough with the centermember in elevation.

In these views, the numeral 1 indicates a shell, preferably of hardenedsteel and ground true and polished and exteriorly tapered to fit a tailstock spindle of a lathe or other machine. The outer end of the shell isenlarged as shown at 2 and threaded to receive a cap 3 which ispreferably knurled exteriorly.

The shell is provided with a tapered socket which terminates anappreciable distance from the inner end of the shell, and this end ofthe shell is formed with a cylindrical bore 4. and a reduced threadedhole 5 which extends from the bore 4 through the end of the shell. Thecenter member is shown at 6, and is tapered to fit the bore and theouter end of the member 6 is formed with a cylindrical reduced part 7terminating in the point 8.

An intermediate portion of the tapered part of the member 6 is reducedas shown at 9 and the interior of the shell is formed with an annularrecess 10 which is in alinement with the reduced part 9 and these partsform an oil chamber and spiral grooves 11 are formed in the member 6 andcommunicate with the oil chamber, and pass to the ends of the taperedportions of the member as clearly shown in Fig. 2.

The cylindrical part '7 passes through a hole in the cap 3 and Washers12 are placed in the space between the cap and the outer end of theshell, to prevent escape of oil and also to prevent entrance of dirt ordust. A thrust plate 13 is placed in the inner part of the bore of theshell and anti-friction means 14 are placed between the plate and theinner end of the center member to act as thrust means, and the plate 13is provided with a stem 15 which extends into the cylindrical part 4 andthis stem is engaged by a bolt 16 threaded in the hole 5 and held inadjusted position by a set screw 17 which passes through a laterallyextending threaded hole formed in the small end of the shell.

As the center member 5 revolves with the work, there is no wear on thepoint of center member nor of work and the machinist is not botheredwith keeping his center oiled and can concentrate his mind more fully onthe work he is doing.

Piston pins and other parts that need to be finished all over can be putin between this antifriction lathe center and the live center of themachine and the friction of the live center against the work will besumcient to drive it while grinding or taking light cuts of turning.

By means of the adjusting screw any wear of the revolving center or ofthe ball thrust bearing can be taken up, thus a minimum amount ofclearance can be maintained between the revolving center and the outsideshell which obviates any looseness or chattering of work while beingmachined.

By careful workmanship, this anti-friction lathe center can be madeabsolutely true, and there being no wear on point of centre, it willremain true.

Its running parts are enclosed and running in oil. Therefore it shouldgive long service and it is also small and compact with no bunglesomeparts in the way of work etc.

It is thought from the foregoing description that the advantages andnovel features of the invention will be readily apparent.

It is to be understood that changes may be made in the construction andin the combination and arrangement of the several parts provided thatsuch changes fall within the scope of the appended claim.

Having thus described my invention, what I claim as new is:-

An anti-friction lathe center comprising a tapered shell having atapered bore extending from a point adjacent the rear or small endthereof through the front end, said small end having a cylindrical boretherein, the outer part of which is reduced and threaded, a centermember tapering rearwardly from a point an appreciable distance from itsfront end to its rear end, the front part of the center member beingreduced and of cylindrical shape and terminating at its front end in apoint, the tapered portion fitting in the shell, a cap threaded on thelarge or front end of the shell and through which the tapered bore and apart of the center member being reduced to form with said recess an oilchamber, and other portions of the tapered part of the member havinggrooves spiral therein in communication with the chamber, and washerslocated between the cap and the front or large end of the shell, saidwashers surrounding the cylindrical part of the center member.

DANIEL G. BRADEN.

